#include <iostream>
#include <queue>
#include <vector>
#include <set>

using namespace std;
typedef long long int LL;
const int coeff[3] = {2,3,5};

int main()
{
	priority_queue<LL,vector<LL>,greater<LL> > pq;
	set<LL> s;
	pq.push(1);
	s.insert(1);
	for(int i=1; ; i++){
		LL x = pq.top();
		pq.pop();
		if(i == 1500){
			cout <<i <<"th ugly number is "<< x <<" ."<<endl;
			break;
		}
		for(int j = 0;j < 3;++j){
			LL t = x * coeff[j];
			if(!s.count(t)){
				s.insert(t);
				pq.push(t);
			}
		}
	}
	return 0;
}
